Apparatus for making hollow pressed axles



Dec. 6,* 1938. E; LANTO APPARATUS FOR MAKING HOLLOW PRESSED AXLES FiledJuly 18, 1936 2 Sheets-Sheet l INVENTOR 42.0942 BY M ATTORNEY Dec. 6,1938. E. LANTO APPARATUS FOR MAKIN HOLLOW PRESSED AXLES 2 Sheets-Sheet 2lfiled July '18, 1936 ATTORNEY flllll/IIII IIII Jlilf Patented Dec. 6,1938 UNITED STATES PATENT OFFICE APPARATUS FOR MAKING HOLLOW PBESSEDAXLES 14 Claims.

The object of my invention is to provide an apparatus by means of whichhollow pressed axles, suitable for use on railroad rolling stock, may bemade. Axles made with my present invention are hollow throughout themajor portion of their. length.

The apparatus includes a two-part .die having a matrix cavity in its twoparts, the shape of an axle, and into the die is placed a round rolledblank equal in diameter to the smallest diameter of the finished axle.The blank is gripped by the die members in the middle and at oppositeends. The blank is also gripped for about thirty-two inches of itslength by retractive members of the die that are wedge controlled.

Punches are provided which are forced endwise into the blank while thelatter is held. in the die and as these punches progress into the hotblank for a distance, say, of about eighteen inches, cross heads carriedwith the punches engage with the wedge-controlled device and graduallyrelease the wedges, permitting the retractive gripping jaws to graduallyrecede flush into the matrix face and-thus permitting the blank to beforced to fill out the size and shape of the matrix face; and thuscausing the blank to be shaped whenfinished, in the shape andproportions of an axle. After the blank has been formed, in the presentapparatus, the journal face portion may be finished oil! on a latheafter the blank is cooled, and ii the finished axle is over-length itmay also be trimmed of! in the lathe.

While this broad object has been sought to be accomplished in the past,certain diificulties arose which previous devices were not capable ofovercoming. It is important that the punches center perfectly at alltimes in relation to the blank and that they have no chance to bendduring the pressing operation. The retractive die members referred toherein are adapted to keep the punches straight and to prevent theirbending or deflect- The punches have a cap on their forward ends ornoses, which are rather elongated to provide a sleeve portion behind thenose of the punches. When the present operation starts, the nose cap andthe sleeve, which is attached to it, both initially move with the punchuntil the sleeve portion is within the axle blank and then the sleeveand the cap on the nose become separated, so

that the sleeve remains adjacent and within one end of the blank whilethe cap progresses with the leading end of the punch until the pressingoperation is completed. Thus the sleeve which is separated from enteringend of the blank to form a the cap remains adjacent the bearing for thepunch at this location.

The excessive friction developed as the punch is pressed into the blankcauses the separation of the sleeve from the cap and this may becontrolled more or less by providing a weakened line where the cap andsleeve join, or by otherwise regulating the thickness of the metal tocause a separation of the sleeve from the cap when sufficient frictionhas been developed.

The sleeve referred to is lubricated inside with graphite to provide alubricated face for the punch to slide upon as the sleeve assumes itsfunction .as a bearing to keep the punch from bending or distorting. Asthe punch progresses into the blank some distance from the bearingformed by the sleeve the punch might otherwise tend to be deflectedexcept for the retractive elements which I provide in conjunction withthe die and which retract gradually within channels of the die as theblank is expanded by the advance of the punch therein. These retractivemembers operating at different points around the axis of the blankresist the expansion of the blank under the action of the punch butgradually recede to allow the blank to be expanded into the cavity ofthe die which determines the size and shape of the exterior of the axle.

By providing these retractive devices operating at difierent locationsaround the axis of the punch, the latter is prevented from deflecting orbending and it is therefore maintained in a'perfectly straight conditionuntil the pressing operation is completed. The apparatus is so designedthat a punch is disposed to enter the blank at each end of the latterand to progress simultaneously into. the blank so that a major portionof the finished axle will be hollow but preferably leaving a middlesection which is solid and which is slightly less in diameter than thewheel carrying portions of the axle.

The punches and their carriers are preferably alike except that theymove in opposite directions and the devices which co-operate to hold thepunch in alignment are the same for both punches or; in other'words, theconstruction is duplicated adjacent opposite ends of the die so thatboth punches perform the same operation on opposite ends of the blankand simultaneously.

By providing the detachable sleeve referred to above, I provide anefllcient bearing for the punch at the entering end of the blank and asstated above thisbearing may be lubricated to reduce friction on thepunch. The retractive members associated with the die form a bearing forthe advancing ends of the punches to prevent deflection or distortion ofthe punches while the pressing operation is being carried out. Thisaction is the same at both ends of the die. The wedge members whichcontrol the retraction of the retractive members are gradually moved inaccordance with the movements of the punch heads so that the retractivemembers move outwardly in proportion to the advance of the punches intothe blank, thereby providing controlled resistance to the deflection ofthe leading ends of the punches.

Other features and advantages of my invention will appear in thefollowing detailed description of the preferred embodiment of myinvention.

In the drawings forming part of this application,

Figure 1 is an elevation of the'principal parts of an apparatusembodying my invention,

Figure 2 is a vertical sectional view on a larger scale, showing aboutone-half the length of the apparatus,

Figure 3 is a similar view, and placedend to end with Figure 2 completesa sectional view of the whole apparatus,

Figure 4 is a longitudinal sectional view of the apparatus on a smallerscale than Figures 2 and 3 but showing the parts in the position at thecompletion of the pressing operation,

Figure 5 is a cross sectional-view taken on the line 5-5 of Figure 2,

Figure 6 is a sectional view taken on the line 8-6 of Figure 4 andtherefore showing the parts at the time the pressing operation iscompleted,

Figure 7 is a perspective view of one of the retractive members detachedfrom the die, and

Figure 8 is a longitudinal sectional view of the cap and sleeve.

The apparatus consists primarily of separable die sections and in thedrawings I have shown the die as consisting of a lower section I whichmay be mounted in any suitable cradle or base, preferably in ahorizontal position, and the upper die section 2 is adapted to rest onthe lower die section, the two meeting along the horizontal line 3. Theupper die section will be detachable from the lower die section for thepurpose of opening the die to discharge the completed axle.

As stated above, the punch mechanism is the same at opposite ends of theapparatus except that they face and move in opposite directions, and adescription of the parts at one end of the apparatus will apply to theparts at the opposite end thereof, and corresponding parts are similarlynumbered except that those at the right hand end of the apparatus in thedrawings will be numbered in prime numbers, whereas the correspondingparts at the other end will be marked in unprimed numbers.

The upper and lower halves of the die are shown as provided with acentral bore 4 which is of different diameters at diiferent locations aswill be pointed out hereinafter, and the blank 5 from which the axle isto be made is placed into the semi-circular cavity of the lower half ofthe die while the upper half is removed and then the upper half of thedie is placed on the lower half to entirely enclose the blank. The blankis introduced into the die while heated to a high degree so that thematerial of the blank may be forced into the cavity of the die by thepunches. The blank, when introduced into the die, preferably hasanexterior diameter equal to 4. Ordinarily, the central portion 6 of thebore ,of the die which co-operates with the middle portion of the blankwill be the portion of smallest diameter of the bore of the die so thatthe blank will, when introduced into the die, be of sufficient diameterto fill this portion of the bore of the die.

The portions 1, 1 of the bore of the die will generally be slightlytapered with the smaller ends of the tapers near the ends of the axle.At 8 there is a laterally extending pocket into which the metal which isto form the flange at each end of the axle may be forced. At 9 I haveshown an annular recess in the two halves of the die into which themetal of the blank may be forced to constitute a flange or shoulder toprovide an abutment on one side of the bearing plates for the axle boxeswhen the axle is assembled in a car truck.

I have shown each punch I0, I carried by a head II, II' in which thebutt or stock l2, I! of the punch is seated and where it is held by aset screw l3, l3. The set screw has a reduced end I4, I 4 which engages,in the peripheral groove l5, l of the punch tolock the punch in thehead. I have shown a driver l6, I6 arranged in a diagonal aperture inthe head II, I I' which is adapted to engage the rear end of the punchfor the purpose of dislodging the punch from the head II, II when theset screw I3, I3 is retracted. This may be desirable because of theexpansion of the butt of the punch due to the heat absorbed by thepunch. It is desirable that the punch be quickly and easily removablefrom the head in order to renew the punches whenever necessary.

' There is also an axial bore l1, l1 in the head II, I l' to permit atool to be inserted to drive against the head of the punch fordislodging it from the head. There is carried by each head H, II' a capI8, l8 which surrounds the punch and which is adapted to act on the endsof the rods l9, IQ for the purpose of moving the wedges to behereinafter described.

There is also provided a centering ring 20 at the outer ends of the die,perfectly to center the punches before they enter the blank. The cap andthe sleeve on the point of each-punch fits closely into this centeringring, so that at the beginning of the punching process there can be nodeviation from true center. But when each punch has advanced until thesleeve has passed this centering ring and the high friction of the hotblank against the sleeve has detached the sleeve from the cap at thehead of the punch, thus forming the inner bearing, a space of aboutone-eighth of an inch remains free between the punch and the centeringring, thus avoiding too great a rigidity in the further course of thetravel of the punch.

This centering ring can slide laterally a small distance into the diehead, so that when the punchesreach the final part of the stroke, theprojecting ends of the blank may be upset to fill out the. space in thedies to form the collar of the journal. I

Theretractingmembers at both ends of the apparatus are the same exceptthat they face in opposite directions and a description of one willapply to both. The retracting members 2| are arranged at diflerentpositions around the axis of the axle and I have shown four of theseretracting members, two of them fitting in the recesses 22 in the upperdie member, and two others the smallest diameter of any portion of theborew dying in the recesses 23 of thelowerdie member.

Each retracting member is shown pivoted at one end upon a pin 24anchored in the die members. The surfaces 25 of these retracting memberswhich face the axis of the axle are curved not only to conform to thecircumferential curvature of the axle but as I have shown theseretracting members operating on a portion of the axle which is taperedthe arcuate surfaces 25 are also tapered in the direction of the lengthof the retracting members. The retracting members have extensions 26near one end which travel in lateral recesses 21 in the die members andwhich prevent lateral displacement of the retracting members and theyalso serve as means with which the wedges co-operate,

The die members are provided with bores 28 extending the length of thedie members, there being as many such bores as there are retractingmembers around the axis of the axle; and these bores are lined withtubes 29 which have cut-outs 30 in which the outwardly extending members23 of the retracting members may move. The extensions 26 on theretracting members have outwardly extending plates 3| which straddle thetubes 29. There is also a groove 32 extending lengthwise along the outersurface of the extension 26 of each retracting member to receive thereina portion of the rod 19 which moves the wedge. The surfaces 33 on theextension 23- on 30 either side of the groove 32 are tapered or madewhich fits closely 0 2and3,the

slanting in relation to the axis of the axle and these are the surfaceswith which the wedges 34 co-operate. Each rod I9 carries a wedge member34 which is substantially D shape in cross section and the wedge has aslanting surface 35 which is parallel with the slanting surfaces 33 onthe retracting members.

I have shown springs 33 arranged in the tubes 29 each having one endabutting against the vertical dividing wall 31 in the tube and havingits other end abutting against one end of the wedge 34. The tendency ofthese springs is to force the wedges 34 in opposite directions or towardthe position where they will engage the surfaces 33 and this actioncauses the rods II to follow the head l3 when the punches are retracted.

In Figure 8 I have shown a cap and sleeve which is applied to the end ofeach punch. This consists of a rounded end portion 33 which fits therounded end 33 of the punch and'this portion of the wall of the memberis preferably about onequarter of an'inch thick. From thisroun'dedor'nose portion extends the sleeve 43 of tubular form, against the outersurface of the punch and the sleeve portion is preferably aboutone-eighth of an inch in thickness, although I do not wish to limit myinvention to any certain measurements. The sleeve portion is preferablyweakened as, for instance, by a groove 4| around the interior surface ofthe sleeve to reduce the metal to about one-tenth of an inch in diameterso that there will be aweakened line circumferentially around the sleevefor the purpose to be described.

Operation While the upper die member 2 is separated from the lower diemember I and while the heads I I, I I are moved away from the die, asshown in Figures hot blank or rod of steel about the smallest diameterof the bore of the die, and which is heated to a high degree, is placedin the cavity of the lower die and then the upper die 2 is placed on thelower die I and secured in any desired manner. The two heads II, II' nowbegin to advance in opposite directions and toward the die so that thepunches with the cap shown in Figure 8 fitted over their free oradvancing ends, start to move into the center of the blank at each end,as shown in Figures. 2 and 3. As the punches are advanced into theblank, the metal of the blank is forced outwardly against the wall ofthe bore of the die, the punches forming hollow spaces or bores in the.opposite ends of the axle blank. In other words, the material of theblank is forced outwardly to fill the portions 1 I of the die and as theblank is of lesser diameter than these portions of the die at thebeginning of the operation the metal displaced by the punches is forcedoutwardly to fill the outer portions 1, I of the die cavity. When thepunches have advanced 'to approximately the position shown in Figure 4,the friction developed between the sleeve and the inner surface of theaxle will have become so great that the forward portion or nose member33 will be separated from the sleeve portion 40 on the weakened line 4!.Thenceforth the sleeve members remain in the axle at about the positionsshown in Figure 4 while the nose portions 38 continue to move with theleading ends of the punches. These sleeve members, remaining in thepositions shown in Figure 4, serve as bearings for the punches at theouter ends of the axle. As the punches continue to move further into theblank, the nose members 33 displace the metal of the axle laterally.

Just before the leading ends of the punches come into line with theleading ends of the retractable members 2| the members l3 make contactwith the rods I9 so that further movement of the heads H, H' cause thewedges 34 to be moved in relation to the surfaces 33 thereby permittingthe retractable members to gradually spread upon their pivots 24 and toswing radially away from the axis of the axle. These wedges are sodesigned that the retractable members offer considerable resistance atvarious points around the axis so that the metal of the blank as thepunches advance, forces the retractable members to swing outwardly aspermitted by the wedges. when the punches have completely advanced intothe blank as shown in Figure 4, the wedges will have com--' pletelydisengaged from the surfaces 33 and the metal of the axle blank willhave been forced out by the punches v are moved to the position shown inFigure 4 where theirinner curved surfaces 25 will conform with the taperof the axle at the portion 42.

At the completion of the pressing operation, the heads II, II" will beretracted in opposite directions to withdraw the punches from the axle.As the members l3 retract, the rods l9 and with them the wedges aremoved in opposite directions by the springs 33 so that by the time thepunches have been completely withdrawn from the die the wedges will bemoved up to the slanting surfaces 33 of the retractable members but theywill not be forced to completely overlap the surfaces 33 until the axlehas been removed from the die.

When the punches are withdrawn from the die and from the axle, the nosemembers 38 will generally remain in the axle because the punches will sothat the'retractable members sleeves so that while the sleeves act asbearing 7 members the friction opposing the inward drive of the punchesis reduced to a negligible degree.

After the punches have been withdrawn from the die the upper die member2 will be removed from the lower die member and the axle may be liftedout of the die member i. As stated above, the axle may be later placedin a lathe and the flanges formed in the pockets 8 may be finished 01fto the correct width and the ends of the axles may be trimmed off toreduce them to uniform length.

While the punches are advancing into the axle in the above describedoperation, the retractable members under the control of the wedges offersuch resistance to the outward swing of the retractable members byacting on the outer surface of the blank and atvarious positions aroundthe axis of the blank, that the leading ends of the punches will not bedeflected, or in other words, the punches will remain straight whileadvancing into the blank and as their leading ends progress further fromthe bearings offered by the sleeves.

Having described my invention, what I claim is:

1. An apparatus for pressing hollow axles, including a two part die ofseparable sections having a cavity to receive therein a blank from whichan axle is to be formed, a punch adapted to be forced axially into theblank held in said die and to force the metal of the blank outwardly toexpand it in the die cavity, and retractable members within the diepivoted intermediate their ends to swing outwardly from the die cavityand having cavity portions against which the blank is forced by thepunch, conforming with the shape of the exterior of the finished axle,said retractable members co-operating with the blank to control theexpansion of a portion thereof while the punch is advancing therein, forthe purpose of resisting deflection of the punch.

2. An apparatus for pressing hollow axles, including a two part die ofseparable sections having a cavity to receive therein a blank from whichan axle is to be formed, a punch adapted to be forced axially into theblank held in said die and to force the metal of the blank outwardly toexpand it in the die cavity, and retractable members within the diepivoted intermediate their ends to swing outwardly from the die cavityand arranged concentrically around the blank, having cavity portionsagainst which the blank is forced by the punch, conforming with theshape of the exterior of the finished axle, said retractable membersco-operating with the blank to control the expansion of a portionthereof while the punch is advancing therein, for the purpose ofresisting deflection of the punch.

3. An apparatus for pressing hollow axles, including a two part die ofseparable sections having a cavity having a tapered portion, to receivea blank from which an axle is to be formed, a punch adapted to be forcedaxially into the blank held in said die and to force the metal of theblank outwardly to expand it in the die cavity, and retractable memberswithin the die pivoted intermediate their ends to swing outwardly fromthe die cavity and having cavity portions against which a taperedportion of the blank is forced by the punch, conforming with theexterior of the tapered portion of the finished axle, said retractablemembers co-operating with the blank to control the expansion of aportion thereof while the punch is advancing therein, for the purpose ofresisting deflection of the punch.

4. An apparatus for pressing hollow axles, including a two part die ofseparable sections having a cavity to receive therein a blank from whichpunch is advancing therein, for the purpose of resisting deflection ofthe punch, and means for automatically controlling the pivotal movementof said retractable members.

5. An apparatus for pressing hollow axles, including a two part die ofseparable sections, having a cavity having a tapered portion to receivea blank from which an axle is to be formed, a punch adapted to be forcedaxially into the blank held in said die and to force the metal of theblank outwardly to expand it in the die cavity at the tapered portionthereof, and retractable members pivoted to the die near the smaller endof said tapered portion to swing outwardly from the die cavity, theinner surfaces of said retractable members conforming with the exteriorof the tapered portion of the finished axle near the tapered portionthereof, said retractable members co-operating with the blank to controlthe expansion of a portion thereof while the punch is advancing thereinfor the purpose of resisting the deflection of the punch.

6. An apparatus for pressing'hollow axles, including a two part die ofseparable sections having a cavity to receive a blank from which an axleis to be formed, a punch adapted to be forced axially into the blank insaid die and to force the metal of the blank outwardly to expand it inthe die cavity, and retractable members forming a portion of the diecavity and pivoted intermediate their ends to swing outwardly from thedie cavity, said retractable members co-operating with the blank tocontrol the expansion thereof while the punch is advancing therein, saidretractable members having inner faces conforming with the exterior of aportion of the finished axle, sliding wedges in said dies forcontrolling the retraction of said retractable members, and means forautomatically operating said wedges.

7. An apparatus for pressing hollow axles, including a two part die ofseparable sections having a cavity to receive a blank from which an axleis to be formed, a punch adapted to be forced axially into the blankheld in said die and to force the metal of the blank outwardly to expandit in the die cavity, and retractable members forming a portion of thedie cavity and pivoted intermediate their ends to swing outwardly fromthe die cavity, said retractable members co-operating with the blank tocontrol the expansion of a portion thereof while the punch is advancingtherein, sliding wedges in said dies for controlling the outwardmovement of the retractable members, and automatic means operated insynchronism with the advancing movement of the punch for operating saidwedges.

8. An apparatus for pressing hollow axles including a two part die ofseparable sections having a cavity to receive a blank from which an axleis to be formed, a punch adapted to be forced axially into the blankheld in said die and force the metal of the die outwardly to expand itin the die cavity, retractable members in said die pivoted intermediatetheir ends to swing outwardly from the die cavity and confined to moveradially in relation to'the axis of the blank, said retractable membershaving arcuate surfaces forming a portion of the die cavity, saidarcuate surfaces adapted to be engaged by the material of the blankforced outwardlyeby the punch, the inner surfaces of the retractablemembers conforming with the shape of a portion of the finished blank,said retractable members co-operating to resist the deflection of thepunch while the latter is advancing into the blank.

9. An apparatus for pressing hollow axles, including a two part die ofseparable sections, having a cavity to receive therein a blank fromwhich an axle is to be formed, punches adapted to be,

forced axially and simultaneously into the opposite ends of the blankheld in said die to force the metal of the blank outwardly to expand itin the die cavity, and retractable members pivoted intermediate theirends to swing outwardly from the die cavity and having inner surfacesshaped -to conform to portions of the exterior of-the finished blank andforming portions of the die cavity adjacent the paths of both of saidpunches, said retractable members co-operating with the blank to preventthe deflection of the punches moving in said blank.

10. An apparatus for pressing hollow axles, including a two part die ofseparable sections having a cavity to receive a blank from which an axleis to be formed, a punch adapted to be forced axially into the blankheld in said die and to force the metal of the blank outwardly to expandit in the die cavity, acap on the advancing end of said punch having acylindrical sleeve extending partly along the punch, said sleeve soformed as to be adapted to be detached from said cap near the end of theblank by friction developed between the punch and the blank whereby saidsleeve will remain in the blank adjacent the end thereof while the punchadvances therein, to form a bearing for the punch while the latter iscompleting its stroke in the blank.

11. An apparatus for pressing hollow axles, including a two part die ofrelatively movable sections, having a cavity to receive therein a blankfrom which an axle is to be formed, a punch having a rounded end adaptedto be forced axially into the blank held in said die, and to force themetal of the blank outwardly to expand it in the die cavity, a memberincluding a rounded cap on the advancing end of said punch and having acylindrical sleeve extending partly along the punch from said cap, saidsleeve portion of said member so formed as to be adapted to be detachedfrom the cap portion by friction developed between the punch and theblank whereby said sleeve will remain in the blank adjacent the endthereof while the punch advances, to form a bearing for the punch whilethe latter is completing its stroke in the blank.

12. An apparatus for pressing hollow axles, including a two part die ofrelatively movable sections having a cavityto receive therein a blankfrom which an axle is to be formed, a punch adapted to be forced axiallyinto the blank held in said die and to force the metal of the blankoutwardly and to expand it in the die cavity, a member comprising a capon the advancing end of the punch and having a cylindrical sleeveportion extending along the punch, said member having acircumferentially weakened portion whereby said sleeve will becomedetached from the cap to remain in the blank near the end thereof byfriction developed between the punch and the blank whereby said sleevewill remain adjacent the entrance end of the blank while the punch is'completing its stroke in the blank, to form a bearing for the punch.

13. An apparatus for pressing hollow axles, including a two part die ofrelatively movable sections having a cavity to receive therein a blankfrom which an axle is to be formed, a punch adapted to be forced axiallyinto the blank held in said die and to force the metal of the blankoutwardly to expand it in the die cavity, a cap on the advancing endof-said punch having a cylindrical sleeve extending along the punch,said sleeve so formed as to be adapted to be detached from said capadjacent the end of the blank by friction' developedv between the punchand the blank, whereby the sleeve will remain inthe blank adjacent theend thereof to form a bearing for the punch while the latter iscompleting its stroke in the blank anda coating of lubricating materialapplied to the interior of said sleeve.

14. An apparatus for pressing hollow axles, including a two part die ofrelatively movable sections having a cavity to receive therein a blank 4from which an axle is to be formed, a punch adapted to be forced axiallyinto the blank held in said die and to force the metal of the blankoutwardly to expand it in the die cavity, a cap on the advancing end ofsaid punch having a cylindrical sleeve extending partly along the punch,said sleeve so formed as to be adapted to be detached from said capwithin the blank and adjacent the end thereof by friction developedbetween the punch and the blank, whereby said sleeve will remainadjacent the entrance end of the blank and form a bearing for the punch,and a bearing member in' which said sleeve primarily engages during thefirst part of the stroke of the punch, whereby said bearing member willform a bearing for said sleeve and said punch prior to the passage ofsaid sleeve into the blank.

EDWARD LANTO.

